Update: This story has been updated to correct the time the Sterling Highway was reopened and to include information about detecting natural gas leaks.

A loud explosion rocked the Diamond Ridge area and the west side of Homer around 10 p.m. last Thursday night.

Kachemak Emergency Services was the primary responding agency for a two-story log home that exploded near Endless View Loop at about Mile 166 Sterling Highway. Firefighters blocked the Sterling Highway at the intersection with Diamond Ridge Road and were not letting vehicles continue. Alaska State Troopers responded at 10:06 p.m., according to an online trooper dispatch, and found debris in the road. KESA’s call out was at 10:20 p.m.

Firefighters on Thursday night said there had been an explosion up the road, but did not have any other information. The road was projected to reopen at 2 a.m. Friday. KESA Chief Bob Cicciarella said the highway reopened about 1:44 a.m.

Alaska State Troopers wrote the cause of the accident is believed to have been a gas explosion. Cicciarella said the indications of a gas explosion are there, but that he can’t confirm that at this time.

“It happened in Kachemak Emergency Services’ district, so they were the primary on scene responders with both fire(fighters) and EMS,” said Samantha Cunningham, Kenai Peninsula emergency services coordinator. “And then there were … tone outs for both (Homer Volunteer Fire Department) and Anchor Point Emergency Services.”

KESA firefighters and medics were not able to start a search right away, Cicciarella said, because there was an active gas leak from the line that had been leading to the house. ENSTAR Natural Gas had to cap off that line before first responders could begin their search for possibly injured people. Cicciarella said KESA got confirmation that the home owner is in the Lower 48 and wasn’t there for the explosion.

According to a Facebook post made by Homer Volunteer Fire Department, there were no reported injuries resulting from the explosion. Homer Electric Association also responded, according to the post.

Natural gas explosions are extremely rare, said Lindsay Hobson, a spokesperson for ENSTAR.

“Natural gas is a very safe fuel source,” she said.” I don’t want people to be concerned about that.”

For natural gas to explode, it has to reach concentrations of between 4 and 15 percent. Natural gas is odorless, but ENSTAR adds a chemical, mercaptan, to make gas detectable. Mercaptan smells like rotten eggs. That odor would be the first sign of a gas leak. The smell would be obvious well below a concentration of 4 percent, Hobson said.

“I tell people to smell, look, listen and leave,” Hobson said about detecting natural gas leaks. “If it smells like rotten eggs, definitely evacuate and give us a call.”

The emergency response number for ENSTAR is 844-SMELL GA(S) or 844-763-5542. Hobson said to call that number before 911 since ENSTAR crews are best equipped to deal with natural gas emergencies.

People also should look for cracks in gas pipes, look for loose connections, check meter connections, and check that vent pipes haven’t come loose, Hobson said. Also listen for hissing gas.

“If you see any signs of a leak, evacuate and then call us,” Hobson said. “Don’t call from inside your home. Even your phone can be an ignition source.”

In the event a resident or business employee returns from being away from a building for some time and smells gas, they also should evacuate and call the ENSTAR emergency line.

At first light on Dec. 28, piles of debris lined the highway for several hundred yards, with large chunks of logs, roofing and foam insulation in the snow. One section of roof got stuck in a tree, and several trees near the house were blown down from the explosion.

The explosion flattened the two-story home, reducing it to a pile of logs. At the scene last Friday, KESA Deputy Chief Joe Sallee said the cause of the explosion remains under investigation.

Since KESA was the main responding agency, it will assume control of the investigation, Cicciarella said. He and another member of the department will conduct it. Cicciarella said there was no evidence of a fire.

“It’s a little more complicated, a little longer investigation time,” he said of the remains of the house. “There’s a lot to sift through for sure, and a lot of pieces to put back together.”

According to online Kenai Peninsula Borough tax records, the house was assessed at $250,000.

Cicciarella said members of KESA did some preliminary investigation, including taking photos of the scene, before one of their firefighters cleared the road of debris.

“At this time no foul play is suspected,” troopers wrote in the online dispatch.

They also wrote that multiple people called to report damage to their own homes because of the explosion.

“It was a significant explosion, that’s for sure,” Cicciarella said.

Reach Michael Armstrong at marmstrong@homernews.com. Reach Megan Pacer at mpacer@homernews.com.

Kachemak Emergency Services Deputy Chief Joe Sallee inspects an exploded house near Mile 166 Sterling Highway on Friday, Dec. 28, 2018, near Homer, Alaska. The debris field from the explosion spread at least 200 feet in all directions. (Photo by Michael Armstrong/Homer News).

Kachemak Emergency Services firefighters blocked off the Sterling Highway at Diamond Ridge Road at about 10:20 p.m. Thursday, Dec. 27, 2018, in Homer Alaska. (Photo by Michael Armstrong/Homer News)

Debris from an exploded house is piled by the road near Mile 166 Sterling Highway on Friday, Dec. 28, 2018, near Homer, Alaska. The debris field from the explosion spread at least 200 feet in all directions. (Photo by Michael Armstrong/Homer News).

Debris from an exploded house lines the road near Mile 166 Sterling Highway on Friday, Dec. 28, 2018, near Homer, Alaska. The debris field from the explosion spread at least 200 feet in all directions. (Photo by Michael Armstrong/Homer News).

A section of a door from an exploded house lies against a backhoe near Mile 166 Sterling Highway on Friday, Dec. 28, 2018, near Homer, Alaska. The debris field from the explosion spread at least 200 feet in all directions. (Photo by Michael Armstrong/Homer News).